The morphology and cell analysis core will serve as a resource for Harvard Skin Disease Research Center investigators to characterize skin-related disorders by various techniques, including: 1) routine histopathology; 2) immunohistochemistry, utilizing both frozen and paraffin-embedded material for both immunoperoxidase and immunofluorescence analysis; 3) in situ hybridization for both frozen and paraffin-embedded tissue sections, utilizing both radioisotope-labeled and biotinylated probes; 4) electron microscopy of epon-embedded cells and tissue sections, and frozen cryosectioned tissue; 5) Fluorescence based flow cytometry and microscopy for quantitative and qualitative analysis of cell surface and intracellular molecules; and 6) photographic or computer-based recording of images derived from 1-5. This core will contain the necessary equipment, reagents, and technical expertise to conduct sophisticated research using the methods described above. Furthermore, personnel in the MCA core will be available to advise investigators on research design and also to assist in the interpretation of results.